,388 Mr. Yarrell oh the Tracheœ of Birds. 



the surface. In its stomach, intestines, and caecal appendages, 

 the Golden Eye is also intermediate, the latter being only 

 two inches in length. In the Goosander these appendages are 

 three inches ; but the size of the bird being considered, reduces 

 them on a comparative estimate to less than two : in the Red- 

 breasted Merganser they are but one inch ; the Smew is without 

 any. In the form of its trachea, the Golden Eye more closely 

 resembles the Mergansers than that of any other Duck, by the 

 enlargement in the tube, and in the shape of the labyrinth, as a 

 reference to Dr. Latham's representations will show. Thus the 

 whole of the numerous species of the Anatidœ appear to descend 

 to the more perfect water-birds by gradations, but with well- 

 marked divisions throughout. 



How far I am correct in an arrangement not strictly in ac- 

 cordance with the published systems of ornithologists, I must 

 leave to better judges to determine ; assuming, however, that 

 an arrangement will be the more natural according to the pro- 

 portion in which it combines ascertained habits, external cha- 

 racters, and anatomical structure*. 



* Tlie following extract is made from the (j8th number of Mons. Tenmiinck'» 

 Planches Coloriées, recently received in this country. Article 40fj. 



HyduobaTES LOBATUS, Tei/nii. 



" Nous avons cru nécessaire de séparer des canards proprement dits, et de réunir 

 sous la dénomination mentionnée, toutes ces espèces à doigt postérieur garni d'un 

 rudiment de membrane, vu que le squelette de ces oiseaux nous offre des différences 

 marquées et constantes ; que leur manière de vivre et le choix des alimens ne sont pas 

 les mêmes que chez les canards à doigt postérieur lisse, et que des caractères faciles à 

 saisir fournissent de très-bons moyens pour établir la différence générique entre ces 

 deux groupes. Nous renvoyons tous les détails sur l'organisation et les mœurs à l'ar- 

 ticle contenant les généralités et l'Index du genre IL/drobate." 



The description of the generic characters and other peculiarities has not yet ap- 

 peared. 



EXPLA- 



